Push button faucets are utilized in a variety of applications, such as in public restrooms where it is desired to have faucets which can be easily activated and which will automatically and positively close after delivering a predetermined volume of water in a set period of time to avoid wasting water and energy. In many states legislation has been passed which sets limits on both the flow rate and the volume of water which can be delivered when a faucet in a public facility is activated. Much of such legislation is based on the ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers) Standard 90-75 which requires that the faucet deliver not more than 0.25 gallons of hot water at a rate not exceeding 0.5 gallons per minute of hot water each time it is activated.
Because of the limited volume of water delivered per activation of the faucet, most faucets in public restrooms are provided with sprayheads which contain small openings which break the outlet flow into multiple streams to insure ample wetting for washing hands. In such sprayhead designs the small openings in the sprayhead are susceptible to plugging from the formation of deposits of lime or other materials dissolved in the water.
The push button faucet of the present invention not only meets the requirements of energy saving legislation based on ASHRAE 90-75, but also includes an improved non-liming sprayhead.